Vapor generator



Sept. 4, 1962 M. FRISCH ETAL VAPOR GENERATOR 3 Sheets-Sheet 1 Original Filed 001;. 8, 1954 INVE/V70R5 D s N mwm w 5%? Na W f m fim ug M ww c ATTORNEY Sept. 4, 1962 M. FRISCH ETAL VAPOR GENERATOR 3 Sheets-Sheet 3 Original Filed 001;. 8, 1954 A TTOE/VFY United States Patent 3,052,222 VAPOR GENERATOR Martin Frisch, New York, and John W. Cartinhour, Baldwin, N.Y., William Tinbergen, North Bergen, N.J., and Tobias Stern, Brooklyn, and George W. Tidd, Manhasset, NY assignors to Foster Wheeler Corporation, New York, N.Y., a corporation of New York Original application Get. 8, 1954, Ser. No. 461,194, new Patent No. 2,944,532, dated July 12, 1960. Divided and this application Dec. 18, 1959, Ser. No. 860,612

6 tClaims. (Cl. 122-476) This invention relates to vapor generators. The present application is a division of applicants pending U.S. patent application Serial No. 461,194 filed October 8, 1954.

The present invention contemplates a novel vapor generator of simple and compact construction and one which provides for low maintenance costs and efiective operation.

In accordance with the present invention a pressure fired vapor generator is provided with a substantially cylindrical shaped combustion chamber defined by a plurality of peripherially arranged vapor generating tubes. A plurality of rows of fluid conducting tubes are arranged outside the combustion chamber and concentric with the vapor generating tubes but in heat exchange relationship with the combustion gases flowing from the combustion chamber. The concentric rows of tubes are arranged in a manner to obtain maximum heating surface of the tubes.

The features and advantages which characterize the present invention Will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein an embodiment of the invention is illustrated by way of example.

FIG. 1 is a sectional View, in elevation, of a vapor generator constituting an embodiment of the present invention and taken on the line 11 of FIGURE 3;

FIG. 2 is a sectional view in elevation, taken on the line 2-2 of FIGURE '3; and

FIG. 3 is a horizontal section taken on the line 33 of FIGURE 1.

Like characters of reference refer to the same parts throughout the several views.

FIGS. 1 to 3 disclose a vapor generator 201 which comprises a cylindrically shaped and vertically disposed casing 202 having insulation 203 on the inside thereof. The top portion of casing 202 is spherical shaped and the bottom portion of the casing is spun into a dished or ellipsoidal shape permitting positive pressurizing of the generator and providing a casing capable of withstanding high pressure without reinforcement. An upper container shown as spherical steam and water drum 204 is arranged in an air space 205 at the upper portion of the generator and the top of the drum projects through an opening formed in casing 202. Disposed in the last-mentioned opening and secured to drum 204 in casing 202 is an expansion joint and seal 206 which permits expansion and contraction of the drum Without causing rupture of the casing and insulation. A pair of downcomer conduits 208 (FIGS. 2 and 3) are connected at their upper ends to drum 204 and at their lower ends to a lower container shown as closed ring shaped or torus supply header 210 which is located adjacent the bottom of casing 202 and coaxial with the longtiudinal axis of the casing. Supply "ice space 215 and has upwardly extending pipes 216 connected thereto along the longitudinal axis.

Oval shaped endless tubes 218 are arranged vertically in casing 202 (FIGS. 1 and 2) parallel to each other, and each tube has a pair of opposite upper and lower arcuate portions and a pair of opposite parallel portions. Each tube 218 is symmetrical, that is, the radii describing the pair of arcuate portions are equal and the parallel portions are equal in length. As seen in FIG. 2, the oval tube 218 disposed along the center line of casing 202 has the largest radii and the radii of the tubes to the left and right of the first-mentioned tube (FIG. 2) decrease gradually so as to form upper and lower dome-shaped or spherical configurations. Tubes 218 are arranged in C011? tact with each other and substantially define a combustion chamber 220 which chamber is closed off at the front by an arcuate insulating wall 221 having a lining 222. Burner openings 223 are provided in wall 221 to accommodate burners, the nozzles 224 of which are shown in FIG. 3. The lower arcuate portions of tubes 218 are each connected to a single pipe 216 whereby the tubes communicate with arcuate header 212 and the upper arcuate portions of tubes 218 are connected to upper pipes 225 which are connected to drum 204. A spherical insulating sheet 226 is arranged on the sides of lower arcuate portions of tubes 218 in the combustion chamber and serves as a floor for the latter. An upper insulating sheet 227 similar to sheet 226, is arranged on the sides of upper arcuate portions of tubes 218 away from the combustion chamber.

Alternate tubes 218 (FIG. 3) to the right of arcuate wall 221 are displaced along a portion of their parallel portions to provide spaces through which combustion gases may flow from the combustion chamber to thereby form a furnace gas outlet 228. A plurality of tubes 230 are connected to supply header 210 and extend upwardly and concentric with the parallel portions of tubes 218, the tubes 230 being connected at their other ends to an upper closed ring shaped or torus header 231 disposed coaxial with lower header 210. Tubes 230 are arranged in a circular manner in contact with the parallel portions of tubes 218, except, at gas outlet 228 where tubes 230 are bent outwardly to form screen tubes and at the rear of the combustion chamber where an opening 232 is provided. Tubes 230 are in contact with each other adjacent opening 232 to prevent passage of combustion gases therethrough. Also connected to torus header 210 are tubes 234 which extend upwardly in the casing and are spaced concentric with the circular rows of tubes 218 and 230 to define an annular gas passage 235. Some of the tubes .234 adjacent gas outlet 228 are bent toward the combustion chamber and act as screen tubes. A curved partition 236 is arranged on the sides of tubes 234 away from the combustion chamber and concentric with the latter and extends counterclockwise from a radial wall 238 (FIG. 3) to a point short of a corresponding radial wall 239 disposed to the left of arcuate header 212. The space between partition 236 and radial wall 239 forms a gas passage outlet 240 which serves to discharge gases from annular passage 235. A plurality of radially aligned tubes 241 are arranged along each longitudinal edge of arcuate wall 221 and are connected to drum 204 at their upper ends (not shown) and to arcuate header 212 at their lower ends, which lower ends are represented by broken center lines (FIG. 3). Adjacent the tubes 241 are a plurality of tubes 2'42 arranged along radial walls 239 and 238 and connected to drum 204- at their upper ends (not shown) and at their lower ends to lower torus header 210. Tubes 241 and 242 are located in annular gas passage 235 and adjacent gas outlets 228 and 240 and function as cooling means for the walls 221, 238, and 239.

A second curved partition or wall 244 is arranged con- 3 centric with baffl'e 236 and spaced from the latter and casing 202 to form a second annular gas passage 245. Wall 244 extends from radial wall 238 counterclockwise (FIG. 3) to radial wall 239 and the gas passage 245 thus formed receives combustion gases from gas passage 235. An opening 246 is provided in wall 244 and communicates with a gas outlet conduit 247 to provide for discharge of the combustion gases in passage 2'45 outside the casing.

A bank 248 of vertical tubes 249 extends in passage 24 from radial wall 238 counterclockwise for almost 180 and a second bank 250 of tubes 251 extends clockwise from radial wall 239 for a short distance in front of gas outlet 240; the tubes 251 of bank 250 having larger diameters than those of the tubes in bank 248. The upper ends of tubes 249 and 251 are connected to torus header 231 While the lower ends of the tubes are connected to torus header 210. Inclined conduits 253 (FIG. 1) are connected to torus header 231 and drum 204 to thereby communicate the tubes 249 and 251 with the drum 204. The tubes 249 and 251 are arranged in radial groups in passage 245 and form annular rows concentric with the combustion chamber 220.

Disposed in the space between banks 248 and 250 in gas passage 245 are a plurality of vertical superheater tubes 255 which are arranged in the passage in the same radial and concentric manner as tubes 2'49 and 251. The superheater tubes 255, however, dilter in shape from that 'of tubes 249 and 251 in that tubes 255 do not have upper ends terminating adjacent torus header 231, but rather, tubes 255 are substantially U-shaped (FIG. 1) and have a return bend or loop adjacent upper torus header 231 'whereby the ends of the tubes are arranged adjacent each other near lower torus header 210. Superheater tubes 255 are arranged in five spaced groups or banks 256, 257, 258, 259, and 260 which banks extend counterclockwise from bank 248 to bank 250. An arcuate superheater header 261 (FIG. 3) is arranged below bank 256 and extends transversely thereof. Header .261 is disposed concentric with the combustion chamber 220 and is connected to the ends of the tubes 255 in bank 256 adjacent partition 236. The other ends of tubes 255 in bank 246 are connected to an arcuate superheater header 262 (FIG. 3) concentric with header 261 and extending below banks 256 and 257. The ends of the tubes in bank 257 adjacent bafiie 2-44 are connected to header 262 and the other ends of the tubes in said bank are connected to an arcuate superheater header 263 (FIG. 3). Arcuate header 263 also extends below bank 258 and is connected to the ends of tubes 255 of said bank adjacent baflle 236 while the other ends of the tubes are connected to an arcuate superheater header 264 (FIGS. 1 and 3) below bank 258. Header 264 also extends below bank 259 and is connected to the ends of the tubes in said bank adjacent bafile 244 while the other ends of the bank are connected to an arcuate superheater header 265. Header 265 extends below bank 260 and is connected to the ends of the tubes in said bank adjacent bailie 236 while the other ends of the tubes in the bank are connected to an arcuate superheater header 266 (FIG. 3) arranged below bank 260. Header 266 is the outlet header for the superheater and an outlet conduit 267 extending through casing 202 is connected to the header and is in communication with steam utilization apparatus (not shown). A steam offtake conduit 268 is connected at one end (not shown) to drum 204 and at the other end to superheater header 261 (FIG. '3) to provide the latter with steam.

From the foregoing, it is apparent that the superheater banks are arranged in series. Steam in header 261 flows upwardly and then downwardly through the tubes of bank 256 into concentric header 262 and from the latter through tubes 255 of bank 245 into header 263. The steam in header 263 flows through the tubes of bank 258 into concentric header 264 and from the latter to the tubes of bank 259 into header 265. From header 265, the steam flows through the tubes of bank 260 into concentric header 4 266 from whence it passes from the superheater through outlet conduit 267.

The arcuate superheater headers are supported by piers 270 (FIG. 1) resting on lower torus header 210 and the superheater headers are maintained out of heat exchange relationship with gases flowing in gas passage 245 by wall 271 (FIG. 1). The top and bottom of annular gas passage 235 is sealed from air spaces 205 and 215 by inclined wall portions 272 and 273, respectively. The top and bottom portions of gas passage 245 are sealed from air spaces 205 and 215 by the integral construction of the concentric walls of partitions 236 and 244 as shown in (FIG. 1). An air inlet 274 is provided in casing 202 (FIG. 3) to supply combustion air to the combustion chamber and air for the air spaces 205 and 215 and the spaces between the insulation 203 and generator elements. The air is for the purpose of cooling the casing and heating the combustion air. Under pressure and of a high density is supplied to the vapor generator through air inlet 274 by apparatus (not shown).

In operation, the vapor generator 201 is started by lighting the burners which causes a stream of gases to flow into combustion chamber 220. The combustion gases in chamber 220 flow out through furnace gas outlet 228 (FIG. 3) into annular passage 235 and travel in a counterclookwise direction in heat exchange relationship with the tubes 230 and 234. The gases in passage 235 discharge from the latter through combustion gas outlet 240 into gas passage 245. In passage 245 the gases flow clockwise in heat exchange relationship with the tubes 251 of bank 250, then the superheater tubes 255, and, finally the tubes 249 of bank 248 after which the gases are discharged through casing gas outlet conduit 247. Feed water is introduced into drum 204 by means (not shown) and the water in the drum flows downwardly through downcomer conduits 208 into lower torus header 210. From torus header 210 the water flows into arcuate shaped header 212 by way of tubes 214 and then is conducted by pipes 216 into oval shaped tubes 218 in chamber 220 where part of the water is changed to steam by radiant heat. The steam in tubes 218 flows upwardly through pipes 225 into drum 204. Water from torus header 210 also flows upwardly through tubes 230 and 234 in gas passage 235 and through tubes 249 and 251 in gas passage 245 in heat exchange relationship with the combustion gases in said passages. The steam thus formed in tubes 230, 234, 259 and 251 is collected in upper torus header 231 from whence the steam is conducted by inclined connecting tubes 253 to drum 204. The steam in drum 204 is conducted to superheater header 261 by 'ofitake conduit 268 and the steam then flows through the tubes 255 of series connected superheater banks 256 to 260 where the steam is superheated by the combustion gases in gas passage 245. The superheated steam from the last bank 260 is collected in outlet superheater header 266 from whence it is discharged from outlet header 266. Water from drum 204 also passes through radially aligned tubes 241 and 242 to cool portions of arcuate wall 221 and radial walls 238 and 239.

While the invention has been shown and described as used for the generation of steam from water, it will be understood that it is capable of use in generating vapor from liquids in general.

Although one embodiment of the invention has been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. Various changes may be made in the design and arrangement of the parts without departing from the spirit and scope of the invention as will be understood by those skilled in the art.

What is claimed is:

1. A vapor generator comprising a casing, a lower liquid container and a upper vapor and liquid container disposed in said casing, a plurality of fluid conducting tubes arranged to substantially define a combustion chamber circular in transverse cross section and oval in longitudinal cross section, said fluid conducting tubes communicating with both said upper container and lower container, and said combustion chamber having a gas outlet, a substantially circular gas passage arranged on the side of the fluid conducting tubes away from the combustion chamber and concentric with the latter, said gas passage being in communication with said gas outlet to receive combustion gases from the latter, a plurality of second fluid conducting tubes arranged in said gas passage in heat exchange relationship with the combustion gases therein and communicating with both said upper container and said lower container, and downco mer conduits communicating the lower liquid container with the upper vapor and liquid container.

2. A vapor generator of claim 1 where each of the firstrnentioned fluid conducting tubes are endless and are in contact with each other.

3. A vapor generator of claim 1 wherein each of the first-mentioned fluid conducting tubes have oppositely disposed arcuate portions described by equal radii and parallel opposite straight portions equal in length.

4. A vapor generator comprising a casing, a lower liquid container and a upper vapor and liquid container arranged in said casing, a plurality of fluid conducting tubes arranged to define a combustion chamber circular in transverse cross section and oval in longitudinal cross section and having a gas outlet, an arcuate partition spaced away from and arranged at the side of the fluid conducting tubes away from the combustion chamber to provide a gas passage, said partition being concentric with the longitudinal portion of the combustion chamber to provide a gas passage in communication with the gas outlet, said partition having a cut out portion to provide for discharge of combustion gases from said gas passage, a plurality of second fluid conducting tubes arranged in said gas passage and in heat exchange relationship with the combustion gases therein, a second arcuate partition spaced from and concentric with the first-mentioned partition to provide a second gas passage, said second gas passage being in communication with the cut out portion in said first-mentioned partition to receive combustion gases from said first-mentioned gas passage, a plurality of third fluid conducting tubes arranged in said second gas passage in rows concentric with each other and with the first-mentioned partition, and downcomer means extending between the lower liquid container and the upper vapor and liquid container and in communication therewith, all of said fluid conducting tubes being in communication with both said upper container and said lower container.

5. A vapor generator having a vertically disposed and substantially cylindrically shaped casing, a plurality of vapor generating tubes arranged to substantially define a vertically disposed combustion chamber circular in horizontal cross section and oval in vertical cross section, said combustion chamber having a gas outlet, means for firing said combustion chamber whereby combustion gases are termed therein, an arcuate partition spaced from and arranged concentric with said vapor generating tubes to provide a gas passage, said gas passage being in communication with said :gas outlet to receive combustion gases therefrom, said arcuate partition having a cut out portion for discharging the combustion gases from said gas passage, a plurality of rows of vapor generating tubes arranged in said gas passage in heat exchange relationshipwith the combustion gases flowing therein, a second arcuate partition concentric with the first mentioned partition and spaced therefrom to provide a second gas passage, said second gas passage being in commu nication (with the cut out portion in said first mentioned partition to receive combustion gases from the first mentioned gas passage, a plurality of third vapor generating tubes and superheater tubes arranged in said second gas passage and in heat exchange relation-ship with the combustion gases therein, a vapor and liquid container arranged in the upper portion of the casing adjacent the top of the combustion chamber, a lower torus header disposed in the lower portion of the casing and in communication with the second and third vapor generating tubes, downcomer conduits communicating the vapor and liquid container with the lower torus header, an arcuate shaped header disposed below the combustion chamber and extending transversely thereof, said arcuateshaped header communicating with the lower torus header and the first-mentioned vapor genera-ting tubes, an upper torus header arranged concentric with the lower torus header and adjacent the top of the combustion chamber, said upper torus header being in communication with the second and third vapor generating tubes and the vapor and liquid container, and means communicating the vapor and liquid container with the superheater tubes.

6. The vapor generator of claim 5 wherein the superheater tubes are arranged in five spaced banks, the opposite ends of the superheater tubes of a bank being arranged adjacent each other and disposed adjacent the lower portion of the second gas passage, said opposite end-s being arranged in two groups, one of the groups being adjacent the first-mentioned partition and the other group being adjacent the second partition, said superheater tubes being bent in a loop intermediate the opposite ends and disposed in the upper portion of said second gas passage, an arcuate superheater header arranged below the first superheater bank and in communication with the vapor and liquid container and with the tube ends of said one group of a first bank, a second arcuate superheater header arranged below the first superheater bank and a second bank, said second arcuate header :being concentric with the first-mentioned header and communicating the tube ends of the second group of the first and second banks, a third arcuate superheater header arranged below the second and third superheater banks and in communication with the tube ends of said one group of the second and third superheater banks, a fourth arcuate superheater header arranged below the third and fourth superheater banks and communicating with the tube ends of the second group of said banks, a fifth arcuate superheater header arranged below the fourth and fifth superheater banks and communicating with the tube ends of said one group of said last-mentioned banks and an outlet arcuate superheater header arranged below and in communication with the tube end of said second group of said fifth superheater bank.

References Cited in the file of this patent UNITED STATES PATENTS 1,917,275 R-ossrnan et al. July 11, 1933 2,009,852 Lum et a1. July 30, 1935 2,688,478 Lykken Sept. 7, 1954 

